Voyager definitely improved once they introduced her character. IMHO it was far superior to Deep Space 9 and Enterprise.
I could have liked Deep Space 9 - if it were not such a blatant rip off of Babylon 5. What, you want to do a sci-fy show about a space station instead of a ship, with a story arc involving an interstellar war, and a show title that ends with a number, and a captain with mystical connections? We can do it too!
Enterprise wasn't bad, but it sure wasn't that good either.
Glad the new Star Trek movie was good, another dog and it would have been a rather bad run.